aws2 uses xml instead of def files aws1+2 cannot be used together"all values in a definition file are now automation strings. This means that they can be simple constant values like float, string, and integer -- or they can be dynamic function calls."

besides some internal things there seem to be no other difference to aws1

It would be cool if CEGUI became the "default" GUI since it has a lot more people focused specifically on its development, and it's rather feature rich already. That would be one less thing to worry about for the devs. Is there any desire to do something like that?